Personally, I subscribe to buying the absolute best sub you can afford, and always keep in the back of your mind to get a second. Even if it takes a year. Even if you have 10 cheap subs, as you said, they’ll never be useful below their range. I’d get the best one you can and start saving. I’m not super familiar with the Canadian market so I can’t help much with a specific sub. Also, don’t worry about timbre matching to LCR. Not an issue.